chore(comments): dep changed from set to map (#10019) [ci skip]

packages/reactivity/src/reactiveEffect.ts

@@ -13,7 +13,7 @@ import {
 // The main WeakMap that stores {target -> key -> dep} connections.
 // Conceptually, it's easier to think of a dependency as a Dep class
 // which maintains a Set of subscribers, but we simply store them as
-// raw Sets to reduce memory overhead.
+// raw Maps to reduce memory overhead.
 type KeyToDepMap = Map<any, Dep>
 const targetMap = new WeakMap<object, KeyToDepMap>()